Wednesday, January 16, 2013

More on the T-34

The T-34 was one of the legendary tanks of WWII. When it appeared in 1941 its combination of firepower, armor and mobility shocked the Germans. However the real performance of the tank was different from the myth that was created for it by Soviet propaganda and German exaggerations.

I have covered the main points in my piece WWII Myths - T-34 Best Tank of the war but I decided to include here some interesting information from various sources.

Ability to maneuver on soft ground

The T-34 had wide tracks which gave it a ground pressure (kg/cm2) of 0.64 for the T-34/76 (assuming 26 tons) and 0.87 for the T-34/85 (at 32 tons). Low ground pressure meant good maneuverability on soft ground (at low speeds) but for many authors it meant that the T-34 could never become stuck in mud. The truth is that the T-34 had the same problems with mud as all other vehicles in the Eastern front.


‘The Das Reich SS Panzer-grenadier Division turned north, advanced on Belgorod, captured the city, and linked up with Grossdeutschland, which had now thrust beyond Tomarovka. Between these two points two German infantry divisions slowly struggled through the mud in their effort to reach the western bank of river. When our counteroffensive had begun there was still some snow on ground, but just before the Armeeabteilung reached the upper course of Donets a sudden rise in temperature created a severe muddy condition. All vehicles except those on the only hard-surfaced road in the area, leading Kharkov to Kursk, became helpless. Our infantry could still slog forty but heavy weapons and artillery were delayed and finally moved up only great effort. Even the T-34s of the Russian rear guards had become embedded to such an extent that we could not retrieve them until warm weather.’

Raus is referring to Manstein’s counterattack in the Ukraine in early 1943.

Reliability

Interesting information on the T-34’s reliability (or lack thereof) during the Kamenets-Podolsky operation (Hube's Pocket) of March-April 1944 is available from ‘Tank Rider: Into the Reich with the Red Army

From page 64

We were happy when tanks from our Brigade's tank regiment caught up with our battalion and we moved on as tank riders. We had just one objective — to capture Kamenets-Podolsk. Running a bit ahead, I would say that it took the Brigade two or three days to arrive at the town. Both people and tanks were tired; the vehicles couldn't take such stress either. Tanks stopped more and more often because of small technical breakdowns, especially broken tracks. Of course we tank riders assisted in tank repairs, so as not to fall behind the battalion.

From page 77

‘We did not have many tanks left, and even those that remained had already used up their engine lifetime and were constantly breaking down. The tank that I was on with my soldiers also broke down. After a day-long stop in a village (we were already in the Western Ukraine), our tank stopped and would not move on. The battalion commander ordered us to stay with the tank and wait for it to be repaired. A day passed by and in the morning the tank crew told us that the breakdown was serious and we were stuck for a long time. I decided not to wait for the completion of the repairs, but to catch up with the battalion on foot.’

From page 79

After a brief rest the battalion received an order to advance and set up defences on the bank of Strypa river in the village of Dobropolie. Further to the west was the town of Bulach, where German reinforcements were starting to arrive. The Brigade was not capable of executing offensive operations. Its personnel was almost gone, almost all equipment was out of action. Out of 450 to 500 tanks of the 4th Tank Army at the beginning of the operation, the entire army only had around 60 vehicles, all with some kind of breakdown.’

The 5-speed gearbox controversy

Initially the T-34 had a 4-speed gearbox. The 4th gear could be used only on a paved road, thus the max cross-country speed was theoretically 25 km/h but in practice it was only 15km/h because changing from 2nd gear to 3rd required superhuman strength.

On later modifications there was a 5-speed gearbox which allowed for a cross country speed of 30 km/h. This equipment supposedly became standard from 1943 onwards.

However it seems that the T-34/85 tanks that were given to the Polish forces in late 1944/early 1945 still had the 4-speed gearbox. T-34: Mythical Weaponby Michulec and Zientarzewski says in page 349:
It was accepted, due to the available information in the subject literature, that the switch to the 5-speed transmission took place in 1943. However, the documents regarding the T- 34-85s delivered during the period end 1944/beginning 1945 (a month after their production) to the Polish forces prove that practically all vehicles had the 4-speed transmission. This applied to tanks produced by the No.183 Factory as much as to the ones produced by the No.112 Factory. The works on the new 5-speed gearbox along with the new main clutch design started in July - August of 1942 and paralleled the development of the T-34S.’

6 comments:

  1. As far as I can remember, Zaloga (T-34 in Action) says that ground pressure of T-34's is :
    – 0,68 kg/cm² for models 1940 and 1941 ;
    — 0,75 kg/cm² for model 1942 ;
    – 0,83 kg/cm² for model 1943 ;
    – 0,85 kg/cm² for T-34-85.

    But T-34 had five road wheels on each side, whereas Pz.-Kpfw. Ⅳ, Panther and Tiger E had eight, and Tiger B, nine. Not all the track links have the same weight onto them, only those on which a roadwheel is passing support an heavy burden.

    Pz.-Kpfw. Ⅳ H had ground pressure of 0,89 kg/cm², and J, of 0,86 kg/cm² ; Panther G : ground pressure = 0,88 kg/cm² ; Tiger B : 1,02 kg/cm².

    Dividing per eight or nine and multiplicating per six ground pressure of German tanks maybe give a better idea, I assume :

    – Pz.-Kpfw. Ⅳ, as if 0,67 or 0,64 kg/cm² and six roadwheels ;
    – Panther G, as if 0,66 kg/cm²… ;
    — Tiger B, as if 0,68 kg/cm²… .

    For T-34 :
    – Model 1943, as if 1,00 kg/cm² and six roadwheels ;
    – T-34-85, as if 1,02 kg/cm²… .

    IS-2 :
    0,82 kg/cm² (six roadwheels).

    Cromwell had ground pressure of some 1 kg/cm² and was five-roadwheeled (same effect than 1,2 kg on six roadwheels ?), Churchill had 1,8 kg/cm² on nine roadwheels (idem) ; Sherman with 75-mm gun and current tracks had ground pressure from 0,93 to 1,01 kg/cm² and six roadwheels ; Sherman with 76-mm gun, VVSS running gear and current width tracks had ground pressure a bit over 1 kg/cm², and c. 0,76 kg/cm² with HVSS running gear and six roadwheels too.

    According to Zaloga (op. cit.), on difficult grounds T-34 could use 55-cm tracks, instead of the current 48-cm ones, reducing ground pressure by some 13 %.

    A booklet in English gave true numbers for Tiger E and Sherman ; if I can read it anew, and have accurate data, I'll comment anew on this subject.

    A website on which Soviet tanks were, are and will be given as perfect ones, whatever reports may conclude, explains that the Aberdeen report of 1943 claiming that T-34 wasn't reliable was disclaimed soon after as ill-reporting by… a GRU agent.

    Game over !

    ReplyDelete
    Replies
    1. ‘Pz.-Kpfw. Ⅳ H had ground pressure of 0,89 kg/cm², and J, of 0,86 kg/cm² ; Panther G : ground pressure = 0,88 kg/cm² ; Tiger B : 1,02 kg/cm².’

      According to Panzertruppen the numbers are:

      Panzer III – for A-D 0.67-0.68, for E-J 0.92-0.97, for L-N 1.02-1.04
      Panzer IV – for A 0.68, for B-D 0.77-0.83, for E 0.91, for F 0.88, for G 0.93, for H-J 0.89
      Panther – for D-A 0.73, for G 0.75
      Tiger I – 0.74
      Tiger II – 0.78

      Next time don't rely on Russia stroooong sites for information.

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    2. Don't worry ! I hope I can distinguish such War-Propaganda-In-Peace-Time websites !

      My sources are, for the British tanks, Cromwell Tank – Vehicle History and Specifications, Bovington Tank Museum, 1983, and Churchill Tank – Vehicle History and Specifications, same publisher ; for the Sherman tanks, website http://afvdb.50megs.com ; for the Tiger E and the Tiger B, Der Panzer-Kampfwagen Tiger und seine Abarten, by Walter Spielberger, Motorbuch-Verlag, Stuttgart.

      The main differences between your figures and mine are for the Panther and the both Tigers : probably your figures are obtained by a comput which mesures the effect of eight or nine roadwheels better than mine do.

      Your website (and those of your links I've already checked) is incredible. I studied History (when I was young !) and I knew few scholars who would be able to be as accurate, about such subjects, than you, an economist, are.

      Each time I read one of your articles, I learn a lot.

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    3. Panzertruppen was written by Thomas L. Jentz

      http://www.amazon.com/Thomas-L.-Jentz/e/B000APB64E

      All his information comes directly from official German reports.

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  2. Spielberger's books were the best ones about German tanks, but Jentz' books are even better.

    Fabio Prado's website says that the ground pressure of a Panther was 0,88 kg/cm². I suppose it's for the Panther G, for it's the same figure I have by some other sources for this version.

    According to the same website, the ground pressure of a Tiger B was 1,03 kg/cm², and the ground pressure of a Tiger E was 1,05 kg/cm² (Spielberger : 1,02 and 1,04 kg/cm²). Its main source is Germany's Tiger Tanks, by Thomas Jentz, however it's not always accurately quoted. Prado's data sometimes differ from those of German war time reports, but the gap is small, when it exists.

    Extract of the article on the Tiger B :
    « The combat tracks, which weighed 3.2 tons each, were 800 mm wide thus providing an acceptable ground pressure (when the tracks sunk to 20 cm) of 0.76 kilograms per square centimeter. »
    So, according to this website, as its author understood Jentz' Germany's Tiger Tanks, ground pressure of Tiger B is 1,03 kg/cm² without penetration, and 0,76 kg/cm² with 20 cm penetration. All the sources I know say that the Tiger B moved far easier on soft grounds than current tanks having ground pressures of 1 kg/cm², that's why I assume the figures given by Jentz in Panzertruppen are from reports taking into account the effect of a better weight repartition due to the number of roadwheels – or so I think. If I can read anew the booklet to which I refered in my first comment, I'll possibly have the answer.

    Your source is a book written by Thomas Jentz, and I don't know anything better about WWⅡ German tanks.

    Yours faithfully.

    ReplyDelete
    Replies
    1. That's correct i had a look and there are figures given on 'ground pressure without sinking in' and 'sinking in 20cm'

      Delete